Fresh from a stunning upset over fourth seed and Philippine Davis Cupper Rolando Ruel Jr., the 16th-ranked Tierro dished out winners to advance against second seed Joseph Victorino.
Victorino, another Davis Cupper who won the Philta Open last April, scored a 6-0, 6-3 over Dapitan City’s Rocky Paglalunan.
"I just played my usual game," said the 6-foot-1 Tierro, who lost to Sabandon in the first round of the PCA Open two years ago, 6-2, 6-0. Tierro, banking on his formidable forehand, breezed through the first set in 25 minutes.
The second set, however, lasted for almost an hour as both players held serve at 4-4 all with Sabandon matching his opponent shot for shot mixed with aggressive set-ups and explosive finishes.